Electrochemotherapeutic cardiac device



Feb. 26, 1963 I H. SCHEIN ETA l 3,078,850

ELECTROCHEMOTHERAPEUTIC CARDIAC DEVICE Filed Aug. 26, 1960 2Sheets-Sheet 1 INV EN TORS Hemqy VSQHEIIY dose-nu 4 5 471 I WE is H.SCH'EIN ETAL 3,078,850

ELECTROCHEMOTHERAPEUTIC CARDIAC DEVICE 2 Sheets-Sheet 2 Feb. 26, 1963Filed Aug. 26. 1960 & k A

He'nwy SCHE'IN dossnu Kara United States Patent M37835!) 1LECTROQHEMQTHERAEEUTIC QARDHA DEVEQE Henry Schcin, West Grange, N1, and.ioscph Keiter, Brooklyn, N.Y., assignors to imperial Electronics, inc,Newark, NJL, a corporation of New Jersey Filed Aug. 26, I960, Ser. No.52,127 3 Claims. ((21. 128-41 3) This invention relates to anelec-trochemotherapeutic cardiac device.

It is the principal object of the invention to provide an improveddevice of the character described which is capable of efficiently andeitectively restarting a stopped heart, i.e. of resuscitating a personwho is literally dead because his heart has ceased to beat.

It is another object of the invention to provide a device of thecharacter described the results of which are far superior to those ofconventional methods now practiced for a similar purpose.

It is another object of the invention to provide a device of thecharacter described which is very light, compact and portable and isextremely easy to employ so that it readily can be carried about by aphysician as part of his emergency kit, or stored in emergency cabinetsin hospitals and like institutions, or made a part of emergencyapparatuses in general.

It is another object of the invention to provide a device of thecharacter described which is sturdy and durable, and can be relied uponto perform at all times and under any circumstances.

It is another object of the invention to provide a device of thecharacter described which constitutes relatively few and simple partsand can be made at a low cost.

It is another object of the invention to provide a device of thecharacter described which applies electric pulses directly to the heartwith the aid of a concurrently injected liquid whereby to minimize theresistance of body tissues in the region of the heart so as to obtainthe maximum effect of the electrical pulses in stimulating a failingheart or restarting a stopped heart.

It is another object of the invention to provide a device of thecharacter described which applies combined electrical and chemicalstimuli to a failing or stopped heart whereby to create a powerfultendency to stimulate a failing heart or start a stopped heart.

It is another object of the invention to provide a device ot thecharacter described which concurrently applies electrical and chemicalstimuli to the heart so that the two stimuli mutually reinforce oneanother and thus are able to create a maximum beneficial result.

It is another object of the invention to provide anelectrocheznotherapeutic method for applying electrical stimuli to theheart under chemical conditions which are favorable for stimulating afailing heart and restarting a stopped heart.

Other objects of this invention in part will be obvious and in part willbe pointed out hereinafter.

The invention accordingly consists in the features of construction,combinations of elements, and arrangements of parts which will beexemplified in the device and method hereinafter described, and of whichthe scope of application will be indicated in the appended claims.

In the accompanying drawings, in which is shown one of the variouspossible embodiments of this invention:

FIG. 1 is a plan view of a hypodermic syringe and hypodermic needlewhich jointly constitute one of the elements of the device embodying thepresent invention;

FIG. 2 is a fragmentary enlarged sectional view of the syringe andneedle, the same being taken substantially along the line of 2-2 of FIG.1, the terminal clip which "ice 2 engages the hub of the needle beingturned for convenience of illustration;

FIG. 3 is a further enlarged sectional view taken substantially alongthe line of 33 of FIG. 2 and illustrating to an exaggerated scale theinsulating sheath which surrounds the cannula of the hypodermic needleat the point where the section is taken;

FIG. 4 is a central sectional view through the body electrode whichconstitutes the second element of the device embodying the presentinvention;

FIG. 5 is a perspective view of a source of electrical pulses whichconstitutes the third element of the device embodying the presentinvention; and

FIG. 6 is a wiring diagram for the source of pulses shown in FIG. 5.

In general, the objects of the present invention are achieved byproviding a device including a hypodermic syringe and a hypodermicneedle, the needle cannula being electrically insulated except at thetip thereof, and said device further comprising a dependable regularsource of electrical pulses which has two output term-inals respectivelyconnected to the hypodermic needle and to an electrode which is adaptedto contact the patients skin.

Referring in detail to the drawings, the reference numeral 10 denotes aconventional hypodermic syringe which is used in accordance with theinstant invention. The particular construction of the syringe is of noimportance and for this purpose there may be employed any syringe thatincludes a barrel, a plunger and means for mounting a hypodermic needleso that the liquid contained in the barrel can be hypodermicallyinjected into a patient through the needle.

The syringe 10 illustrated in the drawings is of a particularly simpletype, constituting a glass barrel 12. and a glass plunger 14 slidablyand closely fitted in the barrel. The bottom wall 16 of the barrel isformed with a bore 18 which extends through the barrel tip 2%, thelatter as is usual being integral with the bottom of the barrel. Saidtip is frustoconical, having a comparatively small taper for effecting aLuer-type coupling with the hub of a hypodermic needle.

It may be pointed out that it is within the scope of the invention touse any other construction of hypodermic syringe, as for example acartridge type syringe, a screw type syringe, a disposable syringe i.e.an ampule type syringe, or a syringe with a metal tip or a lock tip.

Mounted on the syringe tip 2% is a hypodermic needle 22. theconstruction of which is in all respects, save one, conventional. Thusthe hypodermic needle includes a hub 24- having a bore 26 which when thehub is mounted on the tip is in axial registry with the bore 15 of thehypodermic syringe. A hollow tubular shaft, i.e. a canhula, 23 ispermanently secured, eg. by force titting, soldering or brazing, to thehub 24 with its longitudinal passageway 3t) axially aligned with thebore 2d. Although it is conventional, it is desired to note and stressthat at least the cannula 28, and preferably the hub 24 as weil, aremade of an electrically conductive material, that is to say, metal. Thehub 24 includes the usual cylindrical portion 32 which is used inaccordance with the present inv e ntion to act as an electrical contactfor a form of electrical clip soon to be described. However, it shouldbe understood that the specific detail of the electric connectionbetween the pulse source and the hypodermic needle is not critical tothe the proper operation of the invention. Some such connecting meansmust be present; any suitable physical structure can be employedtherefor.

The hypodermic needle 22 of the present invention ditfers from aconventional hypodermic needle in that a substantial portion of thecannula 28 is electrically insulated,

3, races as by an ensheathing sleeve 34 one end of which tenninatesadjacent the sharpened tip 36 of the cannula. Any suitable electricallynon'conductive material of a nontoxic and inert nature can be used, foremmple, any one of the synthetic plastics. Typical appropriate plasticstha can be employed for this purpose are: tliernioplastics such ascellulose acetate, cellulose acetate butyrate, styrene, acrylic resins,polyamide resins, polyvinyl resins and syn thetic rubbers. The sleeve 34can be preformed, as by extrusion, and titted onto the cannula; or itcan be molded in place, or it can be provided by dipping the cannula ina. solvent solution or lacquer of the synthetic plastic with a temporaryprotective coating covering the sharpened tip of the cannula whichprotective coating subsequently is removed to leave the tip bare. Asuitable material for the protective coating is a sterile wax or gum. Ifdesired, there may be employed a synthetic plastic material which iscapable of being autoclaved, i.c. sterilized, at temperatures above theboiling point of water, and for this there can be utilized a high-meltsynthetic thermoplastic or a thermosctting plastic e.g. an alkyd resin,a phenol formaldehyde condensation resin, at urea formaldehydecondensation resin, or a fluorocarbon resin. It will be appreciated thatthe latter materials are usually employed if the hypodermic needle isheat sterilized and the former are used if the needle originally isprepared and ensheathed and packed under sterile conditions and is to beexpendable, i.e. thrown away after a single use.

The end of the sleeve 34 remote from the sharpened tip of the cannulapreferably is located at or adjacent the hub 24 and even may extend ontothe hub, provided. however, that an electrically conductive portion ofthe needle hub is left exposed for contact with one of the output leadsfrom a source of electrical pulses.

In the form of the invention being described and which is illustrated inthe attached drawings, electrical contact is made with the needle hub atthe cylindrical portion 32 by a resilient clip contact terminal 38. Thesame cornprises a yoke of springy electrically-conductive metal e.g. anickel plated Phosphor bronze. The yoke constitutes a base and a pair ofspaced resilient arms. The shape defined by said base and armssubstantially conforms to slightly more than half of the cylindricalsurface of the portion 32, the yoke being smaller than said portion andthereby being able to prehensilely grip the hub of the needle. For thepurpose of expediting coupling of the resilient clip 33 to thecylindrical portion of the needle hub, the tips of the clip arms may beformed with outwardly sloped camming fingers 40.

There is provided as a part of the device embodying the presentinvention a source 42 of electrical pulses. Said source conveniently ishoused in a casing 4-4 to enable it to be more easily carried and toprotect it against the vicissitudes of handling. For example, thehousing may be a rectangular hollow box of synthetic high impact plasticmaterial such as polystyrene modified with a buna- S rubber. Theelectrical components which make up the source of electrical pulses arehoused within the casing 44. Two of said components which soon will bedescribed are switches and the manually manipulatabie members for thesame are external to the casing for easy handling. These two members arean off-on switch knob 46 and a lasislow switch knob 47. Desirably eachof the knobs includes an indicator pointer readable against suitableindicia on the surface of the casing to denote the condition of thecorresponding electrical component. Optionally, a single knob may beprovided which is capable of being set at any one of three positions, afirst of which corresponds to an off condition for the source ofelectrical pulses, a second of which corresponds to a slow condition forthe source of electrical pulses, and the third of which corresponds to afast" condition for the source of electrical pulses. A pair of insulatedwires, 45;, lead from the casing, these being connected within thecasing to the output of the source of electrical pulses. One of thewires, e.g. the wire 48, is connected to the clip 33. The other outputlead is connected to a body electrode 52 which will be described indetail hereinafter.

The specific circuit and electrical components of the source ofelectrical pulses are not critical to the operation of the instantinvention. However said components and circuit must be such that theyare capable of producing upon demand even after long periods ofinaction, a reliable i.c. dependable steady, series of electrical pulsesof a desired amplitude, which preferably are unidirectionel, whichfurther preferably are of comparatively short duration, which furtherpreferably have steep leading wave fronts, which desirably have steeptrailing wave fronts so that the pulses are essentially spike-like dueto their short duration and steep sides, and which essentiaily repeat ata rate lhich approximates the same frequency as the human heart beat,i.c. in the vicinity of 60 electrical pulses per minute.

By way of example there is shown in FIG. 6 a suitable set of electricalcomponents and a suitable circuit 54 for achieving the foregoing ends.The circuit 54 is a simple dependable arrangement which constitutes anastable freerunning two-stage transistor multivibrator with coupledcollectors. Said multivibrator includes a pair of PNP transistors 56,58. In the particular circuit being described the transistors are of theTungsol #342 type. (The specific electrical components that are employedin the circuit will be detailed as to type and values as they arementioned, this being done solely for the purpose of exemplification andwith the understanding that the invention is not to be limited thereby.)

The multivibrator is powered by a small lightweight battery 60, e.g. anEveready #146 battery, which supplies 9.8 volts and has a 350milliampere output. One terminal of the battery 66 is connected to asingle pole single throw off-on switch 62 which is manually actuatableby the knob 46. Said switch selectively applies voltage to one powerlead 64. The other terminal of the battery 66 is connected to the otherpower lead 66.

Lead lines 68, 70 respectively connect the emitter electrodes of thetransistors 56, 58 to the power lead 66.

The base electrode of the transistor 56 is connected by a lead wire 72to a lead wire 74 which is connected to a one-half watt resistor 76having a resistance value of 4700 ohms and which in turn is connected bya lead wire 78 to the power lead 66. The base electrode of thetransistor 58 is connected by a lead wire 80 to a lead wire 82 which isconnected to a one-half watt resistor 84 having a resistance value of4700 ohms and which in turn is connected by a lead wire 86 to the powerlead 66.

The collector electrode of the transistor 56 is connected by a lead wire88 to a lead wire 90 which is connected to a one-half watt resistor 92having a resistance value of 2000 ohms and which in turn is connected bya lead wire 94 to the power lead 64. The collector electrode of thetransistor 58 is connected by a lead wire 96 to a pair of lead wires 98,100 arranged in parallel. The lead wire 98 is connected to a one-halfwatt resistor 102 having a resistance value of 470 ohms. The lead wire160 is connected to a one-half watt resistor 104 having a resistancevalue of 100 ohms. The opposite ends of the two resistors 102, 104 areselectively connectable to a lead wire 106 by a single pole double throwfast-slow switch 108 which is manually actuatable by the knob 47. Thelead wire 106 in turn is connected to the power lead 64.

The junction of the lead wires 88, 90 is connected by a lead wire 110 toa 25 volt 100 microfarad condenser 112 which in turn is connected by alead wire 114 through the lead Wire 80 to the base electrode of thetransistor 58. The junction of the lead wires 96, 98, 100 is connectedby a lead wire 116 to a 25 volt 100 microfarad condenser 120 which inturn is connected by a lead wire 122 through the lead Wire 72 to thebase electrode of the transistor 56.

The output lead wires 50, 48 are respectively connected to the powerlead 66 and to the collector electrode of one or the other of thetransistors 56, 53, as shown, the connection being to the collectorelectrode of the transistor 58.

The foregoing circuit operates as a free running astable multivibrator,upon closure of the switch 62, to generate square Waves 124, i.e.pulses, having a pulse duration of approximately 100 milliseconds. Therepetition rate of said waves when the switch 108 connects the resistor102 in circuit is about cycles per minute. When the switch position ischanged to connect the resistor 104 in circuit the repetition rate isabout 70 cycles per minute, both said rates being within the normalrange of frequency of human heart beats. The pulses 124 have anamplitude of from about 2.5 to 7 volts and a peak current of about 24milliamperes.

To provide the doctor who is operating the device with a visualindication of the repetition rate of electrical pulses being generated apilot lamp, e.g. a gas-filled electric lamp bu'lb 126 may be connectedacross the power lead 64 and the lead line 110. Said lamp is so mountedas to be visible through an opening in the casing 4 5.

The output lead wire 50 is connected to the body electrode 52, thisbeing an electrode such as is conventionally employed forelectrocardiograph operation. For example, the electrode 52 may simplyconstitute a metal plate with a strap to hold it against the body.However, for convenience and speed of use said electrode 52 may comprisea flexible rubber suction cup 128 having a handle 13% wherein there islocated a metal stud 132 to which the lead wire '50 is connected. Thehead of the stud protrudes into the interior of the suction cup so thatwhen the cup is pressed against a persons skin the head of the electrodewill contact the same and thereafter will remain in position until thesuction cup is deliberately released. To minimize contact resistance theoperative face of the suction cup and the head of the stud 132conventionally are coated, prior to use, with a water solubleelectrically conductive paste or unguent.

The device constituting the hypodermic syringe, the hypodermic needleand the source of electrical pulses is adapted to stimulate a failingheart or to restart a stopped heart. The principal use of the device isin an emergency. When such a condition occurs the syringe is filled witha chemotherapeutic cardiac stimulant, e.-g. adrenalin, if it is notalready so filled. The clip 48 is connected to the electricallyconductive hypodermic needle if it is not already so connected and theswitch 46 is turned to on position.

The doctor, either through previous knowledge of the patient or throughhis expert appraisal of the patient when he sees him, estimates whetherfast or slow electrotherapeutic stimuli should be applied and sets theswitch 108 to what he considers the proper position, i.e. fast or slow.'Ihereupon, or even before he energizes the source of electrical pulses,the hypodermic needle is plunged into the patients chest to such anextent that the sharpened tip 36 enters the heart. Then the doctordepresses the plunger 14 to inject adrenalin into the patients heart. Itwill be appreciated that the doctor thus concurrently applies bothchemical and electrical stimuli to the failing or stopped heart.

It has been found that these electroohemotherapeutic stimuli actingconjointly have on several occasions quickly restored normal beatingaction to patients whose hearts have been failing or stopped and sucheificient restoration is believed to have been due to the combinedeffect or" the electrical and chemical stimuli which concurrently actedwith a speed and efiiciency substantially in excess of the speed andetficiency of either of such stimuli used independently.

It will thus be seen that there is provided a device in which theseveral objects of this invention are achieved, and which are welladapted to meet the conditions of practical use.

As various possible embodiments might be made of the above invention,and as various changes might be made in the embodiment above set forth,it is to be understood that all matter herein set forth or shown in theaccompanying drawings is to be interpreted as illustrative and not in alimiting sense.

Having thus described the invention, there is claimed as new and desiredto secure by Letters Patent:

1. An electrochemotherapeutic cardiac device comprising a hypodermicsyringe having a hypodermic needle with an electrically conductivehollow liquid-conducting cannula, an electrically non-conductive sheathsurrounding a substantial portion of the length of the cannula andleaving the tip bare, a source of electric pulses having a voltage inthe order of 2.5 to 7 volts and a peak current in the order of 24milliamperes, said source of pulses having a pair of output terminals,said pulses having a repetition frequency of approximately the samefrequency as human heart beats, circuit means connecting one of saidterminals to said cannula, a body electrode, and circuit meansconnecting the other terminal to the body electrode.

2. A device as set forth in claim.- *1 wherein the source of electricpulses is constructed and arranged to generate pulses having steepleading wave fronts.

3. A device as set forth in claim 1 wherein the hypodermic syringe isloaded with a cardiac stimulant.

References Cited in the file of this patent UNITED STATES PATENTS2,498,882 Fizzell Feb. 28, 1950 2,660,175 Trasher Nov. 24, :19532,924,213 Fleck Feb. 9, 1960 2,979,055 De Beer Apr. 11, 1961 OTHERREFERENCES Leeds: Cardiac Resuscitation, in JAMA, pages 1411- 1413,August 8, 1953.

Harris: Platinum Microelectrode, pages 962-964 of Surgery for June 1960.

1. AN ELECTROCHEMOTHERAPEUTIC CARDIAC DEVICE COMPRISING A HYPODERMICSYRINGE HAVING A HYPODERMIC NEEDLE WITH AN ELECTRICALLY CONDUCTIVEHOLLOW LIQUID-CONDUCTING CANNULA, AN ELECTRICALLY NON-CONDUCTIVE SHEATHSURROUNDING A SUBSTANTIAL PORTION OF THE LENGTH OF THE CANNULA ANDLEAVING THE TIP BARE, A SOURCE OF ELECTRIC PULSES HAVING A VOLTAGE INTHE ORDER OF 2.5 TO 7 VOLTS AND A PEAK CURRENT IN THE ORDER OF 24MILLIAMPERES, SAID SOURCE OF PULSES HAVING A PAIR OF OUTPUT TERMINALS,SAID PULSES HAVING A REPETITION FREQUENCY OF APPROXIMATELY THE SAMEFREQUENCY AS HUMAN HEART BEATS, CIRCUIT MEANS CONNECTING ONE OF SAIDTERMINALS TO SAID CANNULA, A BODY ELECTRODE, AND CIRCUIT MEANSCONNECTING THE OTHER TERMINAL TO THE BODY ELECTRODE.